1. Field of the Invention
The present invention relates to an electronic apparatus including display means for making a display in accordance with a command from control means. In particular, the present invention relates to an electronic apparatus having an electric power saving function, the electronic apparatus including a liquid crystal display unit for illuminating an object with backlight as the display means.
2. Description of the Related Art
Conventionally, a personal computer includes a power supply management function for, in the case where no change occurs with a video image signal, stopping power supply to display means such as a liquid crystal display unit or a CRT (Cathode Ray Tube) to establish a standby state. Conventionally, there have been proposed a variety of techniques relating to power supply management in such a liquid crystal display unit. For example, in Japanese Patent Application Laid-open Nos. 2002-123223 and 2003-271106 or the like, there is proposed a liquid crystal display unit configured to reduce brightness of a backlight based on whether a video image displayed on the liquid crystal display unit is a still image or a moving image.
In the meantime, in recent years, there is a demand for energy saving. An electric power saving function is widely employed for a variety of electronic apparatuses as well as a personal computer. For example, in Japanese Patent Application Laid-open No. 09-139924, there is proposed a video image display unit for carrying out CD ROM reproduction with a music CD and a video image display in which, in the case where a CD to be reproduced is a music CD, power supply of a display system is automatically turned OFF. In addition, in Japanese Patent Application Laid-open No. 2003-050053, there is proposed a fan heater including a liquid crystal display unit having a backlight function, the fan heater supplying hot air into a room, the fan heater being configured to reduce brightness of a light source of the backlight more significantly than during normal operation, while being set in a wakeup timer operation standby mode and a sleep timer operation mode.
As described above, a variety of electronic apparatuses activate an electric power saving function in the case where a no-signal state has continued for a predetermined period of time. Conditions for the electric power saving function to be activated variously depend on functions of each of the electronic apparatuses. Thus, some composite mechanisms including a plurality of functions, for example, some of the composite type television image receivers, each of which has a liquid crystal display unit as display means and which includes a storing and reproducing unit for carrying out reproduction and/or recording of an information recording medium such as a DVD or a hard disk, have a plurality of electric power saving functions which are different depending on their respective functions. Thus, for example, when a user selects a plurality of electric power saving functions, there has been a need for selecting the items on a one by one basis, and there has been inconvenience and a time interval for providing settings so that the user can select a desired electric power saving function. In addition, there has been a problem that operability is impaired, and the user cannot easily select one's desired electric power saving function.